scholarly journals Mycoviruses infecting Colletotrichum spp.: A comprehensive review

2023 ◽  
Vol 83 ◽  
Author(s):  
L. L. Casas ◽  
J. L. Azevedo ◽  
L. N. Almeida ◽  
P. Q. Costa-Neto ◽  
R. A. Bianco ◽  
...  

Abstract Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.

Author(s):  
Mahabeer Singh ◽  
Jitendra Singh ◽  
Shivam Maurya ◽  
Sunil Kumar ◽  
A.K. Meena ◽  
...  

Macrophomina phaseolina (Tassi) Goid. is a soil- and seed-borne pathogen that causes charcoal rot and various rots and blights of more than 500 crop species. Dry root rot (DRR) also called as charcoal rot which causes yield loss ranged from 25-48 per cent. The pathogen is necrotroph and infects a wide range of crops. It is observed that mycelium of M. phaseolina in cotyledons, plumule and radicle, in the naturally infected seeds of mungbean and cowpea. The disease symptoms are clearly visible from the time of emergence and can be evaluated at various stages of development of the plant. The mechanical plugging of the xylem vessels by microsclerotia, toxin production, enzymatic action and mechanical pressure during penetration lead to disease development. Management of M. phaseolina aim to reduce the number of sclerotia in soil or to minimize the contact of the inoculum and the host. Soil solarization can be a cost-effective method for management of soil borne diseases. Disease suppression by biocontrol agents such as Trichoderma harzianum, T. viride and Bacillus subtilis are the sustained manifestation of interactions among the plant, the pathogen, the biocontrol agent, the microbial community on and around the plant and the physical environment and considerably inhibited growth of M. phaseolina. Essential oils and plant extracts contain a multitude of bioactive substances against fungi, bacteria and nematodes. It has been reported that neem oil, turmeric and garlic was effective against M. phaseolina in in vitro condition. Chemical control is an effective method when seed treatment and foliar spray of carbendazim, topsin M-70, captan, thiram, mancozeb, copper oxychloride against root rot and leaf blight (Macrophomina phaseolina) topsin M-70, captan, thiram, mancozeb, copper oxychloride against root rot (Macrophomina phaseolina). As non-chemical alternative methods can be time-consuming and less effective against soilborne plant pathogens. Chemical control is an effective method of controlling some soilborne diseases in agricultural crops. Varoius workers are reported compatibility of biocontrol agents with fungicides and found that Carbendazim and biocontrol agents Trichoderma viride, T. harizianum were found effective under in vitro and pot condition.


Author(s):  
Bharti Umrethia ◽  
Bharat Kalsariya ◽  
Prof. P. U. Vaishnav

In present era, herbal extract succeeds inimitable place in pharmaceutical science. In view back the earliest extraction techniques are lost in the mists of history. As time went the plants have been processed by grinding, boiling or immersing. The systemic presentation of Ayurvedic extraction system has been first time familiarized by Acharya Charaka as Panchavidha Kashaya Kalpana (five basic primary dosage forms) and based upon these primary dosage forms, secondary dosage forms are developed by using different heating pattern for extraction of pharmacological active ingredients. The administration of these dosage forms is mainly dependent on the Bala (strength) of Vyadhi (disease) and Atura (patient). Due to increased demand of Ayurvedic medicines and industrialization, the transformation of classical dosage forms takes place by implanting a wide range of technologies with different methods of extraction include conventional techniques such as maceration, percolation, infusion, decoction, hot continuous extraction etc. and recently, alternative methods like ultrasound assisted solvent extraction (UASE), microwave assisted solvent extraction (MASE) and supercritical fluid extractions (SFE). The extract obtained by these procedure uses as a large source of therapeutic phyto-chemicals that may lead to the development of novel drugs. Essentially, the purpose behind this changing face in both the extraction systems are different but can say that it is a new insight from ancient essence.


2020 ◽  
Vol 5 (1) ◽  
pp. 404-440 ◽  
Author(s):  
Mehrdad Alizadeh ◽  
Yalda Vasebi ◽  
Naser Safaie

AbstractThe purpose of this article was to give a comprehensive review of the published research works on biological control of different fungal, bacterial, and nematode plant diseases in Iran from 1992 to 2018. Plant pathogens cause economical loss in many agricultural products in Iran. In an attempt to prevent these serious losses, chemical control measures have usually been applied to reduce diseases in farms, gardens, and greenhouses. In recent decades, using the biological control against plant diseases has been considered as a beneficial and alternative method to chemical control due to its potential in integrated plant disease management as well as the increasing yield in an eco-friendly manner. Based on the reported studies, various species of Trichoderma, Pseudomonas, and Bacillus were the most common biocontrol agents with the ability to control the wide range of plant pathogens in Iran from lab to the greenhouse and field conditions.


2021 ◽  
Vol 13 (11) ◽  
pp. 2233
Author(s):  
Rasa Janušaitė ◽  
Laurynas Jukna ◽  
Darius Jarmalavičius ◽  
Donatas Pupienis ◽  
Gintautas Žilinskas

Satellite remote sensing is a valuable tool for coastal management, enabling the possibility to repeatedly observe nearshore sandbars. However, a lack of methodological approaches for sandbar detection prevents the wider use of satellite data in sandbar studies. In this paper, a novel fully automated approach to extract nearshore sandbars in high–medium-resolution satellite imagery using a GIS-based algorithm is proposed. The method is composed of a multi-step workflow providing a wide range of data with morphological nearshore characteristics, which include nearshore local relief, extracted sandbars, their crests and shoreline. The proposed processing chain involves a combination of spectral indices, ISODATA unsupervised classification, multi-scale Relative Bathymetric Position Index (RBPI), criteria-based selection operations, spatial statistics and filtering. The algorithm has been tested with 145 dates of PlanetScope and RapidEye imagery using a case study of the complex multiple sandbar system on the Curonian Spit coast, Baltic Sea. The comparison of results against 4 years of in situ bathymetric surveys shows a strong agreement between measured and derived sandbar crest positions (R2 = 0.999 and 0.997) with an average RMSE of 5.8 and 7 m for PlanetScope and RapidEye sensors, respectively. The accuracy of the proposed approach implies its feasibility to study inter-annual and seasonal sandbar behaviour and short-term changes related to high-impact events. Algorithm-provided outputs enable the possibility to evaluate a range of sandbar characteristics such as distance from shoreline, length, width, count or shape at a relevant spatiotemporal scale. The design of the method determines its compatibility with most sandbar morphologies and suitability to other sandy nearshores. Tests of the described technique with Sentinel-2 MSI and Landsat-8 OLI data show that it can be applied to publicly available medium resolution satellite imagery of other sensors.


2017 ◽  
Vol 7 (1) ◽  
pp. 10
Author(s):  
Tatsuya Ohike ◽  
Minori Maeda ◽  
Tetsuya Matsukawa ◽  
Masahiro Okanami ◽  
Shin’ichiro Kajiyama ◽  
...  

Rhizoctonia solani is fungal plant pathogen that infects many different host plants. Recently, biological control agents that are friendly to the environment and ecosystems have attracted much attention as an alternative to the use of chemical fungicide which have been used worldwide to control soil borne pathogens including R. solani. In this study, 53 strains of actinomycetes isolated from environmental soils, and antifungal activities of them were assessed by the dual culture assay. Strain KT showed strong inhibitory activities against 8 phytopathogenic fungi. A great suppressive effect on R. solani growth was observed in the inoculation test of plants using cucumber and chin-geng-sai. In addition, infection of Bipolaris oryzae also could be suppressed in the detached leaf assay using oats. As a result of genetic analysis, it was shown that KT was a species closely related to Streptomyces lavenduligriseus NRRL B-3173T. However, as far as we know, there is no report for biological control agents using S. lavenduligriseus. This study suggests that the strain KT may useful as biological control agents to suppress various crop diseases.


2003 ◽  
Vol 62 (2) ◽  
pp. 393-397 ◽  
Author(s):  
John R. Arthur

There are now concerns that dietary Se intake is inadequate for the population in the UK and parts of Europe. Many different methods can be proposed to deal with this problem. Experience from Finland suggests that the addition of Se to fertiliser is a safe and effective means of increasing the intake of the micronutrient in the human population. However, careful consideration needs to be given to the potential consequences of increasing Se intake. It is important to understand the biochemical and physiological changes that may occur with any increase in Se intake within the UK population. Se is an essential component of at least twenty functional proteins within mammals. These proteins are essential for a range of metabolic functions, including antioxidant activity, thyroid hormone synthesis and immune function. Thus, any increase in Se intake has the potential to influence in a wide range of factors that may impinge on the incidence of chronic disease. Treatment of soil with Se-supplemented fertiliser will certainly increase total Se in food products derived from areas where this treatment is in place. Consumption of such foods will increase Se status in many populations where the existing intake does not meet requirements. If the increases in Se intake are not toxic the overall consequences have the potential to be beneficial.


2013 ◽  
Vol 60 (3) ◽  
pp. 347-364 ◽  
Author(s):  
Cosmin Enache

In a period of very low fertility, effective family and childcare support policy measures are needed. From a wide range of instruments available to government intervention, we focus on public expenditures effects on short-term fertility. Using a sample of 28 European countries in a panel framework, we found that there is a small positive elasticity of crude birth rate to cash benefits related to childbirth and childrearing provided through social security system. Different public services provided to ease the burden of parents and all other benefits in kind, means or non-means tested, are found to be insignificant. These results are robust to alternative methods of estimation. Controlling for country heterogeneity by religion and by culture, some particularly interesting differences in birth rate determinants were highlighted as well.


Author(s):  
Cristina ZEPA ZEPA CORADINI ◽  
Valeriu TABÄ‚RÄ‚ ◽  
Doru PETANEC ◽  
Lavinia MICU ◽  
Irina PETRESCU ◽  
...  

Marigolds have an important economic value which let to an increase production and cultivation being thus used in a wide range of fields. One of the basic elements regarding marigolds production is represented by anthodia with flowers and seeds determined by the blossom and the number of anthodium on the plant. The plant’s blossom is determined by the n umber of lingulate flowers from the external side of the anthodium where seeds grow. Calendula is a polymorphic species, forming during its evolution not only flowering, but also semi-flowering anthodia and simple flowers. In the experimental field of UASVM Timisoara we performed a series of research regarding the morphological features of six local population of marigold from the western part of the country. Flowers’ blooming proved to have a different evolution due to the influence manifested by the local population and also by the harvest results. This blooming phenomenon proved to highly influence the production elements. Blooming influence upon anthodia mass of seeds proved to be as similar as in case of anthodia with flowers. At the beginning of the harvest period, the anthodia mass of seeds proved to be maxim. According to the information collected during research, anthodia flowering fails to reestablish during harvest. The flowering process influences the number and the size of the seeds. Moreover, flowers blooming process may lead to the formation of homogenous seeds, not only in size, but also as regards their morphological aspect. The seeds from the flowering anthodia proved to be homogenous in comparison with other anthodia and had even better technological qualities.


Author(s):  
Belén Rubio Ballester ◽  
Fabrizio Antenucci ◽  
Martina Maier ◽  
Anthony C. C. Coolen ◽  
Paul F. M. J. Verschure

Abstract Introduction After a stroke, a wide range of deficits can occur with varying onset latencies. As a result, assessing impairment and recovery are enormous challenges in neurorehabilitation. Although several clinical scales are generally accepted, they are time-consuming, show high inter-rater variability, have low ecological validity, and are vulnerable to biases introduced by compensatory movements and action modifications. Alternative methods need to be developed for efficient and objective assessment. In this study, we explore the potential of computer-based body tracking systems and classification tools to estimate the motor impairment of the more affected arm in stroke patients. Methods We present a method for estimating clinical scores from movement parameters that are extracted from kinematic data recorded during unsupervised computer-based rehabilitation sessions. We identify a number of kinematic descriptors that characterise the patients’ hemiparesis (e.g., movement smoothness, work area), we implement a double-noise model and perform a multivariate regression using clinical data from 98 stroke patients who completed a total of 191 sessions with RGS. Results Our results reveal a new digital biomarker of arm function, the Total Goal-Directed Movement (TGDM), which relates to the patients work area during the execution of goal-oriented reaching movements. The model’s performance to estimate FM-UE scores reaches an accuracy of $$R^2$$ R 2 : 0.38 with an error ($$\sigma$$ σ : 12.8). Next, we evaluate its reliability ($$r=0.89$$ r = 0.89 for test-retest), longitudinal external validity ($$95\%$$ 95 % true positive rate), sensitivity, and generalisation to other tasks that involve planar reaching movements ($$R^2$$ R 2 : 0.39). The model achieves comparable accuracy also for the Chedoke Arm and Hand Activity Inventory ($$R^2$$ R 2 : 0.40) and Barthel Index ($$R^2$$ R 2 : 0.35). Conclusions Our results highlight the clinical value of kinematic data collected during unsupervised goal-oriented motor training with the RGS combined with data science techniques, and provide new insight into factors underlying recovery and its biomarkers.


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